Unlock device, display a text, then lock again
- by Waza_Be
For the need of my application, I need to display a message on the screen even if the lockscreen is enabled, then wait 3 seconds, than I have to lock again the phone as I don't want it to make unwanted phone calls in your pockets.
First part is easy:
if (PreferenceManager.getDefaultSharedPreferences(
getBaseContext()).getBoolean("wake", false)) {
KeyguardManager kgm = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
boolean isKeyguardUp = kgm.inKeyguardRestrictedInputMode();
WakeLocker.acquire(ProtoBenService.this);
Intent myIntent = new Intent(ProtoBenService.this,LockActivity.class);
myIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
if (isKeyguardUp) {
ProtoBenService.this.startActivity(myIntent);
} else
Toast.makeText(ProtoBenService.this.getBaseContext(), intention, Toast.LENGTH_LONG).show();
WakeLocker.release();
}
With this class:
public abstract class WakeLocker {
private static PowerManager.WakeLock wakeLock;
public static void acquire(Context ctx) {
if (wakeLock != null) wakeLock.release();
PowerManager pm = (PowerManager) ctx.getSystemService(Context.POWER_SERVICE);
wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK |
PowerManager.ACQUIRE_CAUSES_WAKEUP |
PowerManager.ON_AFTER_RELEASE, "CobeIm");
wakeLock.acquire();
}
public static void release() {
if (wakeLock != null) wakeLock.release(); wakeLock = null;
}
}
And the Activity:
public class LockActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Window window = getWindow();
window.addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
window.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
TextView tv = new TextView(this);
tv.setText("This is working!");
tv.setTextSize(45);
setContentView(tv);
Runnable mRunnable;
Handler mHandler = new Handler();
mRunnable = new Runnable() {
@Override
public void run() {
LockActivity.this.finish();
}
};
mHandler.postDelayed(mRunnable, 3 * 1000);
}
}
So, this is nice, the phone can display my text!
The only problem comes when I want to lock again the phone, it seems that locking the phone is protected by the system...
Programmatically turning off the screen and locking the phone
how to lock the android programatically
I think that my users won't understand the Device Admin and won't be able to activate it. Is there any workaround to lock the screen without the Device Admin stuff?
